The Diacetyl Kegging connection, and a nice English Barley Wine

Looking back on over a hundred batches of homebrew, I cannot remember many examples of diacetyl or off-flavors, although I’m sure there were some. Lately, however, I’ve fell into the diacetyl blues. I distinctly recall three different IPAs having diacetyl (one was a black IPA and really buttery). I thought about giving up the hobby forever (yeah right). But seriously, nothing is more disheartening than to pour the first pint of a freshly made IPA, only to be horrified at the muted hop character and the hint of butter or honey off-flavors (diacetyl tastes like butter and fills you up, while a different chemical called pentanedione tastes like honey). These IPAs were nothing like they should taste like, and one became quite bad.

I racked my brain to figure out why. Looking at my brewing practices, the glaring difference was kegging, and I believe I have a theory as to why kegging – specifically, switching from bottling to kegging – might surprise you with diacetyl-laced batches, whereas you didn’t notice it previously. In short: ferment longer than you’re used to. Diacetyl, as we know, is a natural product of fermentation that gets “cleaned up” by the yeast after fermentation is complete. This is why brewers do a “diacetyl rest” for a couple days. With bottling, I believe skipping the diacetyl rest is not a huge problem because the beer goes into a warm environment for another week or two – that’s how it carbonates. In my bottling past, I wonder if the diacetyl was getting cleaned up while carbonating in the bottle. Kegging is totally different. As soon as you cold crash and transfer the beer, the diacetyl is there for good. No more clean up. In summary, I’m pretty sure I’ve been rushing all of my fermentation by a few days. While bottling was saving my ass, kegging is exposing my ass – either way something horrible has been happening to my ass. Having said that, I don’t use yeast starters. That could explain the diacetyl as well. This is just a theory.

In fact, although I hate to admit it, lack of yeast starter could easily be another factor. I hate yeast starters and don’t have the planning skills required to make them. My diacetyl batches just so happened to have liquid yeast, instead of dry yeast (if my memory is correct). Coincidence? probably not. Dry yeast is amazing because it doesn’t require a starter. Liquid yeast doesn’t have enough cells for higher alcohol beers (which I think is stupid). Underpitched, stressed, unhealthy fermentation could cause diacetyl.

My blog has ironically come full circle. My naivety and “this will never happen to me” has been partly exposed, qualified, and humbled.

Homebrewers love Barley Wines but never brew them, and I’m no exception to that rule. Isn’t that weird? The barley wine has a special place in my beer loving heart: it’s huge, malty, complex, and warms you up immediately while you sip it. The American variety is mostly an amped up Double IPA that I don’t like, but the English variety is refined, beautiful, and truly a special beer – it’s more like a whiskey to be honest. It tastes like a beer whiskey to me. And although this Barley Wine was “rushed” through the process – short mash, short boil, no sparge, short fermentation period, no cellaring – it’s still really good. It tastes extremely malty and has that slight alcohol warmth. I’ve read that no-sparge brewing adds to the malt quality of beer – Gordon Strong seems to think so – but I’m not sure if that’s true. This beer will improve with age (if I let it). I don’t think I would change the recipe.


English Barley Wine
14 lb Maris Otter
3.3 lb 2-Row
.6 lb Crystal Medium (Simpsons)
.2 lb Pale Chocolate Malt
1 oz Magnum (FW) 30 minute boil
1 oz Fuggle FO
1 oz Target FO
1 oz EKG FO

started with 8 gallons of water
mashed 148ish for 30
final gravity: 1.020